Auto-immune disorders are thought to have a hereditary predisposition, but the exact mode of inheritance is unclear.
Recent research suggests that dogs with low genetic diversity, such as those with high levels of relatedness between their parents, are more susceptible to auto-immune disease. It is therefore desirable to keep levels of inbreeding as low as possible and feasible within the breed.
Auto-immune disorders that can occur in Havanese include:
Thyroid disease: Auto-immune thyroid disease usually means that the thyroid will be underactive. Symptoms can include coat and skin issues, weigh gain, lethargy, sensitivity to heat/cold. Diagnosis is via blood test to determine the level of the thyroid hormones.
Sabaceous adenitis:This is a disorder that affects coat and skin. The sebaceous glands in the skin are attacked by the body's own antibodies, leading to their inflammation and destruction. Many cases remain undiagnosed, being treated as allergies or other skin disorders. Affected dogs can have dry, flaky skin, hair loss, recurrent ear problems, wet, musty smelling faces, and secondary skin infections. There is no cure. Like all auto-immune disorders, the condition is lifelong and requires careful management.
Immune mediated haemolytic anaemia:This is a severe and often fatal form of anaemia that is caused by the body's own antibodies attacking and destroying blood cells. It can be triggered by a variety of immune stimuli, including viral infections, vaccinations and cancer cells, so anything that stimulates the body to increase its level of immunity/antibodies. Many times the cause/trigger remains unknown.
Allergies: Allergies are quite widespread in Havanese. Whilst they are not 'auto' immune, they are hypersensitivity reactions against a range of allergens, such as pollen of different food allergens. Symptoms may include itching, chewing of paws, sneezing, red, weepy eyes, coat loss and gastrointestinal symptoms.
If you suspect that your dog has an allergy, please get them assessed and tested, so you can avoid the specific triggers if possible.
Patella luxation: Luxating patella is one of the commonest orthopedic disorders in small breeds, including the Havanese. The reported prevalence varies from country to country, with a range of 3-10%. The variation is probably due to different classifications of what is normal. In this condition, the groove in which the knee cap lies is too flat, allowing the patella to slip out. Severe grades are associated with a great deal of pain in the dog. In many European countries, testing for patella luxation in Havanese is mandatory before breeding.
Elbow dysplasia:This is a group of conditions that affect the function of the elbow. The elbow is composed of three different bones, and therefore can be affected by abnormalities in any one of them. One type of condition leading to elbow dysplasia is the short ulna syndrome, where the ulnar bone stops growing, resulting in bowed and shortened front legs, which in turn affects the function of the elbow. Again, this condition can lead to significant symptoms and early onset arthritis.
Hip dysplasia:Hip dysplasia affects many breeds, and you may have heard of it if you have owned pets of other breeds, particularly large breeds, previously. However, unlike patella luxation and elbow dysplasia, hip dysplasia is not a common cause of problems in the Havanese, so unless the hips are very poor, the dogs only infrequently develop symptoms or are adversely affected. Additionally, we do not know what a 'normal' hip score or grade is for Havanese, as not many have been tested in the UK, and different breeds have different normal ranges- so for example the breed mean score for Pugs is 24, whereas the Saluki has a mean breed score of 5. Hip screening in the Havanese is done routinely in the USA, but in most European countries, including the UK, it is not recommended by Havanese breed clubs as essential screening.
For more information on Hip and Elbow schemes, please visit the BVA Canine Health Schemes website.
Ancestral Sleek Coat (Improper Furnishings/Short Hair): One of the most striking features of Havanese is their wonderful, long coat, which was achieved by selectively breeding for long 'furnishings'. Some Havanese, however, have retained the original, ancestral allele that codes for shorter furnishings. Dogs with only one copy of the ancestral allele still appear full coated, but if a Havanese inherits a copy of that allele from both parents, it will have an ancestral sleek coat (erroneously called 'short hair').
These Havanese will still have long hair on their body, ears and tails, but will have shorter, sleek hair on their head and legs.
This is NOT a disease, and these dogs can be otherwise perfectly healthy and happy pets, it is just a different appearance. It is, however, not desirable, as it is a departure from the breed standard.
There is a DNA test for the Improper Furnishings allele, and Havanese can be tested.
The following are some of the disorders known to occur in dogs of different breeds, including occasionally in Havanese.
Havanese should undergo regular eye testing by a veterinary ophtalmologist, to allow early detection of a number of heritable eye disorders.
The Havanese Club of GB advises that Havanese in breeding programs should be tested annually.
Cataracts:Like many other breeds, the Havanese can develop cataracts. Of concern are not those developed in old age, but the juvenile form that affects relatively young dogs, and can lead to blindness. The mode of inheritance is presumed to be mostly recessive, so both parents have to carry the mutation and pass it on to the offspring for cataracts to develop in the offspring. Unfortunately there is no genetic testing for cataracts in Havanese, only clinical eye exams. Sadly, clinical eye exams can only diagnose existing cataracts; eye exams cannot predict which dogs are going to develop the disease in future, and cannot identify carriers.
MRD:Multifocal retinal dysplasia is a progressive disorder of the retina. In many breeds it is a huge problem, causing blindness at a young age. In Havanese MRD does occur occasionally, but tends to be mild and non progressive in this breed, rarely resulting in blindness. Unfortunately, no genetic testing for this condition is available in the Havanese, and again we have to rely on annual clinical eye examination by a specialist.
PRA:Progressive retinal atrophy is a progressive degeneration of the retina at the back of the eye- this condition also leads to blindness. It is not common in Havanese, but can occur from time to time. Again, no genetic testing is available in Havanese.
Other: There are a number of other eye disorders, including Distichiasis- this is a condition where eye lashes grow inside the eye lids. Mild forms are very common in Havanese, although they are not routinely reported in eye tests.
Another relatively common disorder is the Cherry Eye. This is caused by a prolapse of the gland situated in the dog's third eye lid. Because it is a structural defect, the only treatment effective in the long term is surgery.
The Havanese is generally a healthy little dog, with few health issues. However, as is the case in most breeds, there are some inherited conditions that we need to be aware of. Some have very little impact on the ability of the dog to function, but others may be associated with a detrimental effect on the dog's quality of life, and, in some cases, with pain and suffering.
Whilst the Havanese Club of GB recommends annual eye testing, there is no formal health scheme for the Havanese Breed within the British Kennel Club. So strictly speaking, breeders, even Kennel Club Assured breeders, are under no obligation to test their dogs at all. This makes it even more important that you ask to see health testing results (eye test as a minimum) for the parents of the puppy you are about to purchase.
Our Havanese are health tested beyond the minimum recommendation of the Breed Club, and you will always be shown relevant veterinary certificates for both parents.
Cardiac: There are two types of heart conditions that may have a genetic component in some cases- heart murmurs and cardiomyopathy. Heart murmurs are relatively common in puppies, and are often innocent murmurs that the puppies grow out of. However, very loud or complex murmurs, or those that don't disappear by the time the puppy is three or four months, require further assessment of the heart valves by the means of an echocardiogram (heart scan), to exclude valvular disease, particularly of the mitral valve. Murmurs occurring for the first time later in life are more likely to be acquired- they can be caused by infections of the lining of the heart valve, for example.
Cardiomyopathy is a weakening of the heart muscle, leading to heart failure in due course. Cardiomyopathy can be of a hereditary type, or caused by external factors such as viral infections or some medications. If your puppy is suspected to have any heart issues, it is important to consult a specialist, who can perform all tests necessary to determine type and cause of the problem.
Hepatic shunt:Porto-systemic shunts are the most common congenital problem of the liver. There are different types, but in principle the underlying problem is that the blood circulating in the body bypasses the liver instead of flowing through it, so that the liver cannot perform it's detoxifying function on the blood. This means that a variety of protein waste products continue to circulate in the system and cause many long term problems.
Some forms of shunt are operable and can be fully resolved, other are not.
If your puppy is not gaining weight, feeding poorly, has gastrointestinal issues, has neurological symptoms or seizures, discuss bile acid testing with your vet.